The supervisor is creating what is a called a "hostile work environment" for this employee. Creating a hostile work envoronment is indeed a violation of Title VII. There may not be much there in terms of actual damages unless this supervisor is failing to properly compensate, promote, evaluate the employee. I would suggest contacting an attorney to discuss.
The earlier answer is correct, but as a general rule you need more than one incident to have an actionable "hostile environment" case. The supervisor's comment implicates three different discriminatory stereotypes, and that type of person generally makes multiple comments. You should run this by an employment lawyer in your area.
She may be able to file a claim with the Illinois Department of Human Rights especially if this isn't the only issue at work. There is a very strict time to file 180 days so speak with a sexual harassment lawyer at once.